This week, amid the hustling, bustling free-for-all of emerging talent at Miami’s Untitled Art Fair, three paintings hanging at the booth of Chicago’s Monique Meloche gallery seem beamed in from another time and place. Exquisitely rendered portraits that are as calmly assured as the African-American subjects gazing out from their canvases, they are by Amy Sherald, the 44-year-old Baltimore-based artist who rocketed to fame from semi-obscurity this October when the National Portrait Gallery commissioned her to paint Michelle Obama.

Perhaps you would like to buy one? Fat chance—at $50,000 apiece, all three were secured for museums on the fair’s opening day. Anyone who wants a Sherald for themselves has to get at the back of a long and growing line.

For the painter, this week’s success represents the latest peak in a rapid and remarkable climb that is also, one hopes, a model for sustainability in a flash-in-the-pan art market.

An artist who only started her career in earnest in 2012 after recovering from a heart transplant, Sherald exclusively paints portraits of African-American subjects whom she selects for their “quality of existing in the past, present, and future simultaneously,” Meloche explains. That particular quality is so rare and highly particular that she spends much of her time searching for the right models, ultimately casting them off the streets of New Orleans, say, or at her local Baltimore coffeeshop. (The famously imperturbable former First Lady, the dealer said, effortlessly fits this mold.)

Typically, Sherald then pairs her subjects with outfits carefully selected for a similar timeless feel, rendering them in comfortable stances against monochrome backgrounds, cut off at the knee, forthrightly regarding their viewer.

While Sherald is often compared to Barkley Hendricks, the late painter known for his “cool” portraits of stylish African-Americans, another useful precedent is Hans Holbein, the 16th-century Northern Renaissance artist who portrayed the grand figures of his day against similar arresting monochrome colors, from deep blue to minty green. In fact, Sherald was trained in the classical Northern tradition by the Swedish painter Odd Nerdrum, who taught her the old technique of beginning a portrait by modeling the figure in grisaille—now a signature element of Sherald’s style, since she paints all of her subjects with grey skin as a way of “evening the playing field,” Meloche explains.

Because her process is so sedulous and time-consuming—she only paints 10 to 12 portraits per year—demand for Sherald’s work has outstripped supply from the beginning. In 2015, when Meloche included a painting by the artist in a group show, it sold immediately for $8,500, together with another one in her studio. That led to a solo show at the gallery in 2016, which quickly sold out, spawning a 20-person waitlist.

This spring, when the gallery held a pop-up show on New York’s Lower East Side, five paintings sold to collectors on the list for $35,000. The bump up to $50,000 for the fair—Sherald’s first major showing since the Obama news—is “a little leap,” Meloche admits, but is in line with the market for her work, considering that the waitlist has expanded to some 50 people. The museums acquiring the portraits at the fair came off that list, she added.

Indeed, the institutional attention for Sherald’s painting is growing apace. Works are already in the collections of the Nasher Museum of Art and the Smithsonian’s National Museum of African American History and Culture, where Meloche says her portrait is one of the “most photographed paintings in the museum.” This coming February, the artist’s Obama portrait will debut at the National Portrait Gallery, before having her first big museum show at the Contemporary Art Museum St Louis in May.

That, however, is just the warm-up: Christopher Bedford, the curator who organized Mark Bradford’s Venice Biennale pavilion, will organize a major retrospective of Sherald’s paintings at the Baltimore Museum of Art in 2020, celebrating the artist in her hometown.

Not bad for an artist whose output only numbers some 30 canvases to date.